#!/usr/bin/env python
#
#  Copyright (c) 2013 SWITCH http://www.switch.ch
#
#  Licensed under the Apache License, Version 2.0 (the "License");
#  you may not use this file except in compliance with the License.
#  You may obtain a copy of the License at
#
#      http://www.apache.org/licenses/LICENSE-2.0
#
#  Unless required by applicable law or agreed to in writing, software
#  distributed under the License is distributed on an "AS IS" BASIS,
#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
#  See the License for the specific language governing permissions and
#  limitations under the License.
#

import argparse
import os
import subprocess
import sys

__version__ = '1.0.1'

# default ceph values
CEPH_COMMAND = '/usr/bin/ceph'

# nagios exit code
STATUS_OK = 0
STATUS_WARNING = 1
STATUS_ERROR = 2
STATUS_UNKNOWN = 3

def main():
    # parse args
    parser = argparse.ArgumentParser(description="'ceph df' nagios plugin.")
    parser.add_argument('-e','--exe', help='ceph executable [%s]' % CEPH_COMMAND)
    parser.add_argument('-c','--conf', help='alternative ceph conf file')
    parser.add_argument('-m','--monaddress', help='ceph monitor address[:port]')    
    parser.add_argument('-i','--id', help='ceph client id')
    parser.add_argument('-n','--name', help='ceph client name')
    parser.add_argument('-k','--keyring', help='ceph client keyring file')
    parser.add_argument('-d','--detail', help="show pool details on warn and critical", action='store_true')
    parser.add_argument('-W','--warn', help="warn above this percent RAW USED")
    parser.add_argument('-C','--critical', help="critical alert above this percent RAW USED")
    parser.add_argument('-V','--version', help='show version and exit', action='store_true')
    args = parser.parse_args()
   
    # validate args
    ceph_exec = args.exe if args.exe else CEPH_COMMAND
    if not os.path.exists(ceph_exec):
        print "ERROR: ceph executable '%s' doesn't exist" % ceph_exec
        return STATUS_UNKNOWN
    
    if args.version:
        print 'version %s' % __version__
        return STATUS_OK
    if args.conf and not os.path.exists(args.conf):
        print "ERROR: ceph conf file '%s' doesn't exist" % args.conf
        return STATUS_UNKNOWN
    
    if args.keyring and not os.path.exists(args.keyring):
        print "ERROR: keyring file '%s' doesn't exist" % args.keyring
        return STATUS_UNKNOWN
    if args.warn > args.critical or not args.warn or not args.critical:
        print "ERROR: warn and critical level must be set and critical must be greater than warn"
        return STATUS_UNKNOWN
    
    # build command
    ceph_df = [ceph_exec]
    if args.monaddress:
        ceph_df.append('-m')
        ceph_df.append(args.monaddress)
    if args.conf:
        ceph_df.append('-c')
        ceph_df.append(args.conf)
    if args.id:
        ceph_df.append('--id')
        ceph_df.append(args.id)
    if args.name:
        ceph_df.append('--name')
        ceph_df.append(args.name)
    if args.keyring:
        ceph_df.append('--keyring')
        ceph_df.append(args.keyring)
    ceph_df.append('df')
    #print ceph_df
    
    # exec command
    p = subprocess.Popen(ceph_df,stdout=subprocess.PIPE,stderr=subprocess.PIPE)
    output, err = p.communicate()
    
    # parse output
    # print "DEBUG: output:", output
    # print "DEBUG: err:", err
    if output:
        # parse output
        # if detail switch was not set only show global values and compare to warning and critical
        # otherwise show space for pools too
        result=output.splitlines()
        # values for GLOBAL are in 3rd line of output
        globalline = result[2]
        globalvals = globalline.split(' ')
        # strip all empty values from list
        globalvals = [x for x in globalvals if x != '']
        # prepare pool values
        # pool output starts in line 4 with the bare word POOLS: followed by the output
        poolline = result[3:]
        # print 'DEBUG:', globalvals
        # finally 4th element contains percentual value
        # print 'DEBUG USAGE:', globalvals[3]
        global_usage_percent = globalvals[3]
        global_available_space = globalvals[1]
        global_total_space = globalvals[0]
        # print 'DEBUG WARNLEVEL:', args.warn
        # print 'DEBUG CRITICALLEVEL:', args.critical
        if global_usage_percent > args.critical:
            if args.detail:
                    poolline.insert(0, '\n')
                    poolout = '\n '.join(poolline)
            else:
                    poolout = ''
            print 'CRITICAL: global RAW usage of %s%% is above %s%% (%s of %s free)%s' % (global_usage_percent, args.critical, global_available_space, global_total_space, poolout)
            return STATUS_ERROR
        elif global_usage_percent > args.warn:
            if args.detail:
                    poolline.insert(0, '\n')
                    poolout = '\n '.join(poolline)
            else:
                    poolout = ''
            print 'WARNING: global RAW usage of %s%% is above %s%% (%s of %s free)%s' % (global_usage_percent, args.warn, global_available_space, global_total_space, poolout)
            return STATUS_WARNING 
        else:
            print 'RAW usage %s%%' % global_usage_percent
            return STATUS_OK
    elif err:
        # read only first line of error
        one_line = err.split('\n')[0]
        if '-1 ' in one_line:
            idx = one_line.rfind('-1 ')
            print 'ERROR: %s: %s' % (ceph_exec, one_line[idx+len('-1 '):])
        else:
            print one_line
    
    return STATUS_UNKNOWN
if __name__ == "__main__":
    sys.exit(main())
